Basic studies of isolation of uncultured iron-oxidizing bacteria, and mechanism of forming iron oxides produced by the bacteria for producing novel functional materials.

• Project/Area Number: 15H06654
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Applied microbiology
• Research Institution: Japan Women's University
• Principal Investigator: Suzuki Tomoko 日本女子大学, 理学部, 助教 (30623772)
• Project Period (FY): 2015-08-28 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000); Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2015: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 鉄酸化細菌 / Leptothrix ochracea / Gallionella ferruginea / 細菌 / 鉄酸化 / 微生物 / 難培養性細菌

Outline of Final Research Achievements

In this study, I aimed to isolate and look for a culture methods for iron oxidizing bacteria that produced tubular or corkscrew-shaped iron oxides outside the cell, and then, to clarify the mechanism of formation of uniquely-shaped iron oxides. I searched for the habitat of iron-oxidizing bacteria, and I found a well with floating brownish flocs consists of tubular iron oxides. However, I did not get permission for sampling. On the other hand, the corkscrew-shaped iron oxides obtained from enrichment culture of Gallionella ferruginea were analyzed by using LM, SEM, SEM-EDX, HRTEM-FFT. Shortly-pitched long fiber iron oxides formed in the synthetic medium with different shape, structure and elemental composition from naturally-formed the corkscrew-shaped iron oxides. FFT pattern with few spots indicates microcrystalline. Our results showed that novel functional materials could be produced through culturing in different media.

Research Products

• [Journal Article] Abiotic deposition of Fe complexes onto Leptothrix sheaths (2016)
  • Author(s): Tatsuki Kunoh, Hideki Hashimoto, Ian R. McFarlane, Naoaki Hayashi, Tomoko Suzuki, Eisuke Taketa, Katsunori Tamura, Mikio Takano, Mohamed Y. El-Naggar, Hitoshi Kunoh, Jun Takada
  • Journal Title: Biology Volume: 5(2);26 Pages: -
  • DOI: 10.3390/biology5020026
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Biological and physicochemical characters and functions of amorphous iron oxides produced by iron-oxidizing bacteria at ambient temperature in hydrosphere (2016)
  • Author(s): Jun Takada, Hideki Hashimoto, Tomoko Suzuki, Hitoshi Kunoh
  • Journal Title: Journal of the Japan Society of Powder Metallurgy Volume: 63(10) Pages: 869-875
  • Peer Reviewed
• [Journal Article] Direct adherence of Fe(III) particles onto sheaths of Leptothrix sp. strain OUMS1 in culture (2016)
  • Author(s): Tatsuki Kunoh, Hideki Hashimoto, Tomoko Suzuki, Naoyuki Hayashi, Katsunori Tamura, Mikio Takano, Hitoshi Kunoh, Jun Takada
  • Journal Title: Minerals Volume: 6(1) Pages: 1‐15
  • DOI: doi:10.3390/min6010004
  • Peer Reviewed / Open Access
• [Presentation] 鉄酸化細菌Gallionella ferrugineaがつくる酸化鉄の材料特性と培養による酸化鉄材料生成 (2016)
  • Author(s): 鈴木智子
  • Organizer: BICシンポジウム2016 バイオ周辺領域とイメージングとの関わり
  • Place of Presentation: 東京都 日本女子大学
  • Year and Date: 2016-10-22 – 2016-10-22
  • Invited
• [Presentation] Structural and physicochemical analyses of iron oxides produced by iron oxidizing bacteria Gallionella ferruginea and Leptothrix ochracea (2015)
  • Author(s): Tomoko Suzuki
  • Organizer: Interuniversity Workshop on Biological Responses to External Stimuli
  • Place of Presentation: 東大阪市、近畿大学
  • Year and Date: 2015-12-15
  • Invited
• [Presentation] 鉄酸化細菌がつくる酸化鉄の構造と物理化学的解析 (2015)
  • Author(s): 鈴木智子，橋本英樹，久能均，高田潤
  • Organizer: 2015年度日本地球化学会年会，特別セッション「S02 鉄の地球微生物学と地球化学」
  • Place of Presentation: 横浜市、横浜国立大学
  • Year and Date: 2015-09-17
  • Invited